ISUZU KB P190 2007 Workshop Repair Manual

Engine Mechanical – V6 Page 6A1–24
Page 6A1–24
Camshaft Drive System
Three timing chains are fitted:
• primary (1),
• right-hand secondary (2), and
• left-hand secondary (3), refer to Figure 6A1 – 18 for the HFV6 engine.
The primary timing chain connects the crankshaft sprocket (4) with the left-hand and right-hand intermediate drive shaft
sprockets (5).
Each oil pressure fed intermediate sprocket drives the se condary timing chains, which subsequently drive the respective
cylinder head camshaft position actuators (6).
Two stationary timing chain guides (7) and movable timing c hain shoes (8) control secondary timing chain backlash.
Each secondary timing chain shoe is under tension from an oil pressure hydraulically operated tensioner (9). To control
backlash on the primary chain, two st ationary timing chain guides (10) and an oil pressure hydraulically actuated
tensioner with built in shoe (11) are fitted.
The tensioners minimise timing chain noise and provide accura te valve action by keeping slack out of the timing chains,
while continuously adjusting for timing chain wear. The tensioners incorporate a plunger that adjusts outward with wear,
minimising backlash. The tensioners are equipped with oiling jets to spray oil onto the timing components during engine
operation. Each tensioner is sealed to the head or block using a rubber coated steel gasket. The gasket traps an
adequate oil reserve to ens ure quiet start-up.

Figure 6A1 – 18
Legend
1 Primary Timing Chain
2 Secondary Timing Chain, Right-hand
3 Secondary Timing Chain, Left-hand
4 Crankshaft Sprocket
5 Intermediate Sprocket
6 Camshaft Sprocket 7 Secondary Timing Chain Guide
8 Secondary Timing Chain Shoe
9 Secondary Timing Chain Tensioner
10 Primary Timing Chain Guide
11 Primary Timing Chain Tensioner


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ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–25
Page 6A1–25
1.5 Engine Lubrication System
Lubrication Description
A structural diecast aluminium oil pan is fitted that incorporates an oil suction pipe, an oil deflector and an oil level
sensor. The oil suction pipe is bolted in to the oil pan and seals to the bottom of the cylinder block with a gasket. The oil
deflector is bolted to the upper portion of the oil pan and ensures oil supply is maintained under all conditions. The oil
level sensor is mounted thr ough the bottom of the oil pan.
A crankshaft driven gerotor oil pump is mounted to the front of the cylinder block. The pump, which incorporates an
internal pressure-relief valve, draws oil from the oil sucti on tube through the lower passage in the cylinder block. Oil is
then directed through an upper passage to the left-hand side of the cylinder block where the oil filter adapter is mounted.
The oil filter adapter incorporat es a top-access, cartridge style oil filter. The filter is accessed through a screw-on cap tha t
incorporates an oil bypass valve. The o il filter adapter housing incorporates a drain back control valve and a threaded oil
pressure sender. Oil flows through a lower passage within the oil filter adapter and through the o il filter cartridge. Filtered
oil travels back through the upper passage of the adapter and into the engine block.
Oil is then directed up and across the front of the cylinder block, through several drilled passages. These front passages
feed oil to each cylinder head, the passage for the main bearings and piston oil jets, the right-hand and left-hand
secondary idler sprockets and to t he primary timing chain tensioner.
Each cylinder head passage directs oil into oiling circuits for the stationary hydraulic la sh adjusters (SHLAs) and the
camshaft bearing journals. An additional passage in the cy linder head also directs oil to the secondary timing chain
tensioner.
The oil passage that supplies oil to the main bearings also s upplies oil to pressure actuated piston cooling oil jets. Each
oil jet is mounted between opposing cylinder bores and directs oil to the two bores to provide extra cooling and control
piston temperatures.
From the front passages, oil is directed to the front of the block where t he right-hand and left-hand intermediate drive
shaft sprockets and the primary timing chain tensioner are mounted. Each camshaft timing chain tensioner relies on a
gasket to maintain an oil rese rve after the engine is turned off. All camshaft timing chain tensioners incorporate a small
oil jet to supply an oil spray onto the camshaft timing chain components.
Oil returns to the oil pan, either through the camshaft timing chain area or through the drain back passages on the
outboard walls of the cylinder heads and cylinder block.

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ISUZU KB P190 2007

Engine Mechanical – V6 Page 6A1–26
Page 6A1–26
1.6 Service Notes
Cleanliness and Care
Throughout this Section, correct cleaning and protection of machined surfaces and fr iction areas is a part of the repair
procedure. This is considered standard workshop practice, even if not specifically stated.
When any internal engine part is serviced, care and cleanliness is extremely important.
When components are removed for service, they should be ma rked, organised or retained in a specific order for
reassembly.
At the time of installation, components should be installed in the same location and with the same mating surface as
when removed.
Any engine is a combination of many machined, honed, polished and lapped surfaces with tole rances that are measured
in thousandths of a millimetre. Thes e surfaces should be covered or protected to avoid component damage.
A liberal coating of clean engine oil should be applied to fricti on areas during assembly, as the lubrication will protect and
lubricate friction surfaces dur ing the initial engine start-up.
Replacing Engine Gaskets
Re-Using Gaskets and Applying Sealants
• do not reuse any gasket unless specified,
• gaskets that can be reused will be ident ified in the service procedure, and
• do not apply sealant to any gasket or sealing surf ace unless specified in the service information.
Separating Components
• Use a rubber mallet to separate components.
• Bump the part sideways to loosen the components.
• Bumping should be done at bends or reinforced areas to prevent distortion of parts.
Cleaning Gasket Surfaces
• Where required, remove all gasket and sealing materi al from the part using a plastic or wood scraper.
• Care must be used to avoid gouging or scraping the sealing surfaces.
• Do not use any other method or technique to re move sealant or gasket material from a part.
• Do not use abrasive pads, sand paper, or power tools to clean the gasket surfaces as these methods of cleaning
can cause damage to the component sealing surfaces. Abrasive pads also produce fine grit that the oil filter cannot
remove from the oil. This grit is abrasiv e and has been known to cause internal engine damage.
Assembling Components
• When assembling components, use only the sealant specified or equivalent in the service procedure.
• Sealing surfaces should be cl ean and free of debris or oil.
• Specific components such as crankshaft oil seals or valve stem oil seals may require lubrication during assembly.
• Components requiring lubrication will be i dentified in the service procedure.
• When applying sealant to a component, apply the am ount specified in the service procedure.
• Do not allow the sealant to enter into any blind threaded hol es as it may prevent the bolt from clamping correctly or
cause component damage when tightened.
• Only ever tighten bolts to the correct to rque specification. Do not over-tighten.

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Engine Mechanical – V6 Page 6A1–27
Page 6A1–27
Use of Room Temperature Vulcanising and Anaerobic Sealer
CAUTION
A number of sealant types are commonly
used in engines. Examples are; room
temperature vulcanising (RTV) sealer,
anaerobic gasket eliminator sealer, and
anaerobic thread sealant and pipe joint
compound. The correct type of sealant and
amount must be used in the specified location
to prevent oil leaks. Do not interchange the
different types of sealers.
Room Temperature Vulcanising Sealer
• Room temperature vulcanising (RTV) s ealant hardens when exposed to air. This type of sealer is used where two
non-rigid parts (such as the intake manifold and the engine block) are assembled together.
• Do not use RTV sealant in areas where extreme temper atures are experienced. These areas include the exhaust
manifold, head gasket, or other surfaces w here a gasket eliminator is specified.
• Follow all safety recommendations and di rections that are on the container.
• To remove the sealant or the gasket mate rial, refer to Replacing Engine Gaskets.
• Apply RTV to a clean surface. Use a bead size as specified in the service procedure. Run the bead to the inside of
any bolt holes. Do not allow the sealer to enter any bli nd threaded holes, as it may prevent the bolt from clamping
correctly or cause damage when the bolt is tightened.
• Assemble components while RTV is still wet (within 3 minutes). Do not wait for RTV to skin over.
• Tighten the bolts to the correct torque specification. Do not over-tighten.
Anaerobic Sealer
• Anaerobic gasket eliminator or thread sealant, hardens in t he absence of air. This type sealer is used where two
rigid parts (such as castings) are assembled together, w here fasteners are subjected to vibration, or where the
holes are not blind. When two rigid parts are disassembled and no sealer or gasket is readily noticeable, the parts
were probably assembled using a gasket eliminator.
• Follow all safety recommendations and di rections that are on the container.
• To remove the sealant or the gasket mate rial, refer to Replacing Engine Gaskets.
• Apply a continuous bead of gasket eliminator to one flange or on the bolt/stud thread. All surfaces must be clean
and dry.
• Spread the sealer evenly to achieve a uniform coating on the sealing surface.
• Do not allow the sealer to enter any blind threaded holes as it may prevent the bolt from clamping correctly or
cause damage when tightened.
CAUTION
Anaerobic sealed joints that are partially
tightened and allowed to cure more than five
minutes may result in incorrect shimming and
sealing of the joint.
• Tighten the bolts to the correct torque specification. Do not over-tighten.
• After correctly tightening the fasteners, remove t he excess sealer from the outside of the joint.

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Engine Mechanical – V6 Page 6A1–28
Page 6A1–28
Pipe Joint Compound
• Pipe joint compound is a pliable sealer that does not comp letely harden. This type of sealer is used where two non-
rigid parts (such as pressed steel and ma chined surfaces) are assembled together.
• Do not use pipe joint compound in areas where extreme temperatures are expected. These areas include the
exhaust manifold, head gasket, or other surfaces where gasket eliminator is specified.
• Follow all safety recommendations and di rections that are on the container.
• To remove the sealant or the gasket mate rial, refer to Replacing Engine Gaskets.
• Apply the pipe joint compound to a clean surface. Use a bead size or quantity as specified in the procedure. Run
the bead to the inside of any bolt holes. Do not allow the s ealer to enter any blind threaded holes as it may prevent
the bolt from clamping correctly or caus e component damage when the bolt is tightened.
• Apply a continuous bead of pipe joint compound to one seali ng surface. Sealing surfaces to be resealed must be
clean and dry.
• Tighten the bolts to the correct torque specification. Do not over-tighten.
Separating Parts
CAUTION
Many internal engine components will
develop specific wear patterns on their
friction surfaces. When disassembling the
engine, internal components must be
separated, marked and organised in a way to
ensure reinstallation in their original location
and position.
Separate, mark, or organise the following components:
• Piston and the piston pin.
• Piston to the specific cylinder bore.
• Piston rings to the specific piston.
• Connecting rod to the crankshaft journal.
• Connecting rod to the bearing cap.
• Crankshaft main and connecting rod bearings.
• Camshaft and rocker arms.
• Rocker arms and stationary hydraulic lash adjusters to cylinder head location.
• Valve to the valve guide.
• Valve spring and shim to the cylinder head location.
• Engine block main bearing cap location and direction.
• Oil pump drive and driven gears.
Tools and Equipment
Special tools are listed and illustrated throughout this Section with a complete listing at the end, refer to 7 Special Tools.
These tools (or their equivalents) are specially designed to quickly and safely accomplish the operations for which they
are intended. The use of these special tools will also minimise possible damage to engine components. Some precision
measuring tools are required for inspec tion of certain critical components. A commercially available torque wrench and
torque angle wrench, Tool No. EN-7115 are required for the correct tightening of various fasteners.
To correctly service the engine assembly, the following items should be readily available:
• Approved eye protection and safety gloves.
• A clean, well-lit, work area.
• A suitable parts cleaning tank.
• A compressed air supply.
• Trays or storage containers to keep parts and fasteners organised.
• An adequate set of hand tools.
• Approved engine repair stand.
• An approved engine lifting device that will adequatel y support the weight of the components.

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Engine Mechanical – V6 Page 6A1–29
Page 6A1–29
Fasteners
Fasteners are central to the reliable operation of an engine.
Whenever any bolt or any other threaded component is
removed, allow the engine to cool (inset A) before
attempting fastener removal.
Because of the greater the rmal expansion of aluminium,
bolt threads will change dimensi on to a greater extent when
hot with this material (inset B) when compared to cast iron.
If a bolt or other threaded com ponent is removed before the
engine is allowed to cool to at least 50 ° C, threads could be
pulled from the cylinder block or cylinder head.
Do not use impact tools to remove bolts during engine
disassembly. While this may be common practice with cast
iron engine components, use of thes e tools is more likely to
pull the aluminium threads in the cylinder block or head of
this engine.

Figure 6A1 – 19
Clamp Load
When torque is applied to a fa stener, the fastener stretches
and the joint compresses. The force developed in the
fastener due to its stretch is called tension (C), while the
force applied to the joint is called clamp load (B).
As shown, only a small portion of the applied torque (A) is
transferred to the clamp load (inset 1). Friction under the
bolt head (inset 3) and in the threads (inset 2) absorbs
much of the applied torque (A). Typically, only 10% (inset 1)
of the torque is available to develop stretch (or tension) in
the fastener and clamp load in the joint.
Therefore, a slight variation in friction in the thread or under
the bolt head, results in a wide variation in the clamp load
applied to the joint.

Figure 6A1 – 20
Torque Angle and Torque to Yield Fasteners
The torque angle method of applying torque to a fastener has been developed to overcome the effects of friction
variation in fastener applications.
The application of the torque angle method does not always mean the fastener has to be replaced after loosening. It is
only when the fastener has been angle tightened to the extent the yield point has been exceeded, that the fastener must
be replaced.
Examples are the main bearing caps that are angle tightened but the bolts can be re-used, whereas the M11 cylinder
head bolts that are torque to yield fasteners, must be replaced after loosening.

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Engine Mechanical – V6 Page 6A1–30
Page 6A1–30
2 Diagnosis
2.1 Engine Diagnosis
Begin engine mechanical system diagnosis by reviewing the disassembled views provided in 1.2 Engine Components
and 1.4 Engine Construction . Reviewing the description and operation info rmation provided will assist in determining
whether the condition described by the custom er is a fault or normal engine operation.

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Engine Mechanical – V6 Page 6A1–31
Page 6A1–31
2.2 Symptoms
Strategy Based Diagnosis
1 Review the system operations to familiarise yourself with the system functions, refer to 1 General Information and
6C1-1 Engine Management General Information.
2 Perform an engine management Diagnostic System Check, refer to Section 6C1-2 Engine Management – V6 –
Diagnostics .
All diagnosis on a vehicle should follow a logical process. Strategy based diagnosis is a uniform approach for repairing
all vehicle systems. The strategy based diagnostic flow chart may always be used to resolve a system problem. The
diagnostic flow chart is the place to start when repairs are required. For a detailed explanation of strategy based
diagnosis and the flow chart, refer to Section 6C1-2 Engine Management – V6 – Diagnostics .
Visual / Physical Inspection
1 Inspect the vehicle for aftermarket accessories which may adversely affect engine operation.
2 Inspect the easily accessible or visible system components for obvious signs of damage or conditions that may cause the symptom.
3 Check the engine lubrication system for the following:
• correct oil level,
• correct lubricant viscosity,
• correct oil filter application, and
• contaminated or burnt oil.
4 Confirm the exact operating conditions under whic h the fault occurs. Note factors such as:
• engine speed (r.p.m.),
• ambient temperature,
• engine temperature,
• engine warm-up time, and
• vehicle road speed.
5 Compare the engine sounds, if applic able, to a known good engine, and ensure you are not trying to diagnose a
normal operating condition.
Intermittent
For intermittent faults, test the vehicle under the same conditions the customer reported in order to confirm whether the
system is operating correctly.

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Engine Mechanical – V6 Page 6A1–32
Page 6A1–32
2.3 Engine Misfire without Internal Engine
Noises
Cause Correction
Abnormalities, severe cracking, bumps or missing areas in
the accessory drive belt.
Abnormalities in the accessory drive system and/or
components may cause engine speed variations that result
in a misfire diagnostic trouble code (DTC). A misfire code
may be present without an ac tual misfire condition. Replace the accessory drive belt, refer to 3.5 Accessory
Drive Belt.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs.
Worn, damaged or misaligned accessory drive components
and excessive pulley run-out may lead to a misfire DTC.
A misfire code may be present without an actual misfire
condition. Inspect the components and repair or replace as required.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs.
Loose or incorrectly fitted flexplate or crankshaft balancer
assembly.
A misfire DTC may be present without an actual misfire
condition. Repair or replace the flexplat
e or crankshaft balancer as
required, refer to 3.13 Crankshaft Balancer Assembly or
4.3 Flexplate Assembly.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs
Restricted exhaust system.
A severe restriction in the exhaust flow can cause
significant loss of engine performance and may set a DTC.
Possible causes of restrict ions in the exhaust system
include collapsed/dented pipes and blocked mufflers and/or
catalytic converters. Repair or replace exhaust syst
em components as required,
refer to 8B Exhaust System.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs
Incorrectly installed or damaged vacuum hoses. Repair or replace vacuum hoses as required.
Incorrect sealing between the intake manifold and cylinder
heads, upper intake manifold and lower intake manifold,
throttle body and intake manifold. Repair or replace the intake
manifold, throttle body gaskets,
cylinder heads, throttle body as required.
Incorrectly installed or damaged barometric
pressure(BARO) sensor and/or seal. The seal should not
be torn or damaged. Repair or replace the BARO sensor and/or seal as
required, refer to 6C1-3 Engine Management – V6 –
Service Operations.
Incorrectly installed or damaged EVAP purge solenoid
and/or O-ring seal. Repair or replace the EVAP purge solenoid and/or seal as
required, refer to 6C1-3 Engine Management – V6 –
Service Operations
Worn or loose stationary hydraulic lash adjusters (SHLA)
and/or rocker arms.
The SHLAs, rocker arms and roller bearings should be
intact and in the correct position. Replace the SHLAs and/or rocker arms as required, refer to
3.21 Stationary Hydraulic Las h Adjuster or 3.20 Rocker
Arm.
Stuck valves.
Carbon build up on the valve stem s can result in the valves
not closing correctly. Repair or replace as required, refer to 3.22 Cylinder Head
Assembly.
Excessively worn or misaligned timing chain/s. Replace the timing chain/s and components as required,
refer to 3.16 Timing Chains, Tensioners, Shoes and
Guides.
Worn camshaft lobes. Replace the camshaft/s and SHLAs as required, refer to
3.19 Camshaft or 3.21 Stati onary Hydraulic Lash Adjuster.
Excessive oil pressure.
A lubrication system with ex cessive oil pressure may lead
to excessive lash adjuster pump-up and loss of
compression. 1 Perform an oil pressure tes
t, refer to 3.1 Engine Oil.
2 Repair or replace the engine oil pump as required, refer to 3.17 Oil Pump Assembly.

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Engine Mechanical – V6 Page 6A1–33
Page 6A1–33
Cause Correction
Faulty cylinder head gasket and/or cracking or other
damage to the cylinder head and cylinder block coolant
passages.
Coolant consumption may or may not cause the engine to
overheat. 1 Inspect the spark plugs for
coolant saturation, refer to
6C1-3 Engine Management – V6 – Service
Operations.
2 Inspect the cylinder heads, cylinder block and/or head gaskets, refer to 3.22 Cylinder Head Assembly
and/or 4.7 Cylinder Block.
3 Repair or replace components as required.
Worn piston rings.
Oil consumption may or ma y not cause the engine to
misfire. 1 Inspect the spark plugs for oil deposits, refer to 6C1-3
Engine Management – V6 – Service Operations.
2 Check the cylinders for a loss of compression, refer to 2.15 Engine Compression Test.
3 Perform compression testing to identify the cause of
low compression.
4 Repair or replace components as required.
A damaged crankshaft reluctor wheel.
A damaged crankshaft reluctor wheel can result in different
symptoms depending on the severity and location of the
damage.
Systems with severe relu ctor ring damage may exhibit
periodic loss of crankshaft posit ion, stop delivering a signal,
and then re-sync the crankshaft position.
Systems with slight reluctor ring damage may exhibit no
loss of crankshaft position and no misfire may occur,
however, a DTC may set. Replace the crankshaft as required, refer to 4.6 Crankshaft
and Main Bearings.
Refer to 6C1-2 Engine Management – V6 – Diagnostics to
check for DTCs

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